A wide variety of different approaches have been known in the manufacturing of heating torch tips. These have included attachments for cutting torch tips, as well as the heating torch tips, per se. For example, about the best prior art tips were those that employed milled external cuts or splines on the exterior of a mold that could be moved to an exact position longitudinally of a master outer tip and then pinned into place. This was very costly in manufacture as well as requiring exact emplacement and then drilling through circular shells. Once the pins were worn, the respective tip had pieces that were loose and rattled and in severe cases could blow out. Of course other torch tips having formed apertures therein are known but did not perform as well as the above described tip construction. Moreover, the old style forming of the exterior milled cuts or splines caused burrs. The burrs in turn were difficult to clean and potentially could create hot spots so the possibilities of pre-ignition of the gas within the tip became possible. Moreover, the burrs interiorly of the tip, if not throughly cleaned, caused uneven flame and a tip that did not perform satisfactorily.
In addition, a wide variety of machine-type heating torches have been known. These type heating torches had structure that might seem superficially similar but, in fact, did not function and could not be employed as in this invention.
The most pertinent art of which applicant is aware in the published literature are formed by the following United States patents issued to co-workers and assigned to the assignee of this invention. These patents are: U.S. Pat. Nos. 4,022,441, Turney, "UNIVERSAL TORCH"; 4,200,235, Monschke, "MULTIPLE PIECE TORCH TIP"; 4,248,384, Zwicker, "CUTTING TORCH WITH SINGLE DRILLED PASSAGEWAYS"; 4,314,672, Madewell et al, "BEVELING TIP". Even the technology and innovation in these improved tips were directed more at cutting torches and did not provide the answers which the heating torch tip of this invention provides.